It's really strange, your problem and your solution!
Let me know this : XMM was freezing will all script or only with IMDB one? Because if the website is "down" or too slow, sometimes XMM freeze. Maybe you have re-install and after this time the website was come back online!
Well, i definitely tried many different scripts (same ones i've been using), and still got the window that just sat there like it froze. And as soon as i reinstalled over it, it works fine again. Don't know why that is, but at least i discovered a solution for it, and hopefully for others that have also ran into this problem.